The video ends with Harris saying he is losing his breath to which a deputy replies, "F*** your breath."

WARNING graphic video

Harris was taken to a local hospital where he later died. Tulsa County Sheriff's Office said Bates intended to incapacitate Harris using a stun gun as he was being subdued, but accidentally took hold of his pistol and fired that instead.

A Tulsa Police Sergeant who investigated the shooting said Bates suffered a stress-induced phenomenon known as "slips and capture", which led him to believe he was holding a Taser when opening fire.

Prosecutors are now to decide whether to file criminal charges. The clip of the 2 April 2015 incident was released by the Tulsa County Sheriff's Office after a request by Harris's family that it be made public.

It comes just days after a bystander filmed South Carolina officer Michael Slager shooting unarmed suspect Walter Scott eight times in the back, as he attempted to flee after being stopped because his car had a broken light.

The footage re-ignited nationwide outrage at police and their perceived excessive use of force against African-Americans that followed the killings Michael Brown, 18, in Ferguson, Missouri and Eric Garner, 43, in New York City.